High-pressure steam-boiler plant for portable engines



April 23, 1931- o. H. HARTMANN 1,802,421

S I BY HIGH PRESSURE STEAM BOILER PLANT FOR PORTABLE ENGINES Filed Aug. 16, 1927 INVENTOR ATTORNEYS Patented Apr. 28, 1931 um'rso STATES PATENT OFFICE OTTO H. HARTMANN, F CASSEL-WILHELMSHOHE, GERMANY, ASSIGNOR TO SCHMIDTSCHE HEISSDAMPF-GESELLSCHAFT M. B. 31., 0F GASSEL-WJ LHELMSHOHE, GERMANY, A-CORPORATION OF GERMANY i HIGH-PRESSURE scream-Boreas PLANT roR PORTABLE ENGINES Application filed August 16, 1927, Serial No.

My invention relates to a steam boiler plant of a portable or travelling character which supplies steam for an engine having a plurality of stages operating at different pressures. The plant has been designed especially for use in conjunction with locomotives having two boilers, particularly of that type in which one of said boilers is a water tube boiler formed by the fire box, for generating extra high-pressure steam of at least 30 atmospheres, while the other is a horizontal boiler constructed as a cus-v tomary fire tube boiler generating livesteam of the usual pressure of 10 to.15 atmospheres, utilizing the heat of the gases emanating from the fire box.

In this type of locomotive, the high-pressure steam is conveyed from the steam space of the water tube boiler to a high-pressure cylinder and is expanded therein to the pressure which prevails in the fire tube boiler. The steam which exhausts from the cylinder, is mixed with the live steam of the fire tube boiler, and ledinto the low-pressure cylinder, the exhaust steam of which escapes in the usual .manner through theblast pipe of the locomotive. Preferably, the live steam of either boiler is superheated on its way to its respective cylinder. The superheater tubes may be arranged within the lire tubes in any well-known manner.

In a locomotive boiler plant of this type it sometimes occurs that the steam develop ment in the high-pressure boiler is much greater than in the low-pressure boiler so that thepressure in the high-pressure boiler exceeds the pressure in the low-pressure boiler by more than a predetermined amount. I Especially during the heating-up period when the locomotive is not yet ready for operation and, consequently, the steam inlet to the high-pressure cylinder is closed, the allowable pressure limit in the water tube boiler is reached before the pressure in the fire tube boiler has risen to the amount necessary for the operation of the locomotive. Therefore, provision mustbe made for relieving the.,water' tube boiler of the sur lus of steam"tleveloped.

n object of the invention is an arrange- 213,285, and in Germany January 28, 1924.

ment whereby high-pressure steam is with-- drawn from the high-pressure boiler and utilized for raising the pressure in the lowpressure boiler. By this arrangement a proper proportioning of the steam-pressures developed in the boilers takes place and the loss of heatenergy which would result from blowing-ofi' the surplus through the customary safety valve is avoided.

More particularly, the invention refers to the provision of a conduit leading from the steam space of the high-pressure boiler to the water space of the low-pressure boiler, and of the valve in said conduit. By this ar-, rangement high-pressure steam may be conpressure boiler and mixed with the water, thereby imparting its heat to the same and accelerating the development of low-pressure steam. This arrangement has the advantage over that by which the high-pressure steam is conducted into the steam space of the low-pressure boiler, in that the surplus of heat contained in the high-pressure steam is instantaneously transmitted to water of the low-pressure boiler so that uniform temperature conditions are maintained within said low-pressure boiler.

A further object of the invention is the provision of the above mentioned valve with a handle, which is manually adjustable from the engineers cab of the locomotive.

In the accompanying drawings, Fig. 1 is a longitudinal section of a locomotive engine embodying my present improvement; Fi 2 represents on an enlarged scale the longtudinal section of the manually operated valve for conveying steam from the highpressure boiler to the water space of the lowpressure boiler; and Fig. 3 shows in a view similar to that of Fig. 2, but illustrates a modified embodiment of the valve, namely an automatically operating valve having a spring-controlled seating member.

In Fig. 1 a locomotive of the above described type is diagrammatically represented. As this locomotive is fully shown and described in my co-pending application, Serial N 0. 737,311, filed September .12, 1924, Patent N 0. 1,700,480, of which this applicaducted into the water space of the lowtion is a continuation in part, only a brief description of the construction will be given.

The boiler plant comprises two boilers generating steam of different pressures. The one is a high-pressure boiler A comprising water tubes d forming a closed circuit with a heating coil h arranged within a steam drum 6. The tubes d form the walls of the fire box. Within this closed circuit a medium, e. g. water, heated by the burning fuel, circulates and transfers its heat to the water in the drum 6 thereby developing highpressure steam. As no claim is at present drawn to the details of the boiler construction, no view, in cross-section, showing the closed circuit is included in the drawings. Adjacent to the fire box A the low-pressure boiler B, constructed as a'fire tube boiler, is arranged. The high-pressure steam developed in the water tube boiler A is conducted from the steam drum 6 through a conduit Z to a superheater, the pipes C of which are located in the usual manner within the fire tubes of the low-pressure boiler B. The steam developed in the low-pres sure boiler is conveyed from the steam space thereof through a pipes to a second superheater D, the tubes of which are also located within the fire tubes of the low-pressure boiler B. The" superheated high-pressure steam flows from the superheater C through a pipe at into the high-pressure cylinder 6 of the engine. The low-pressure steam is led by means of a conduit m from the superheater 1) into the low-pressure cylinder F of the engine. As the high-pressure cylinder when viewed in elevation, is in a position in which it is located behind the low-pres sure cylinder, the low-pressure cylinder is shown partly broken away thereby making the high-pressure cylinder partly visible.

The invisible part of the same is indicated by dotted lines. The exhaust steam of the low-pressure cylinder escapes through a conduit 9 leading to the blast pipe r. The drum 6 of the water tube boiler A is fed with water, for instance, through pipe 11; by means of a pump H to which water is supplied from the water space of the low-pressure boiler B by means of a pipe 4).

According to the invention means are provided for carrying" steam from the high pressure boiler to the water space of the low-pressure boiler B. In the construction illustrated in Fig. .1, a valve housing t is mounted on the steam drum 6 and in communication with the same. conduit u controlled by valve member a, leads from the valve housing to the low-pressureboiler B and is arranged in such amanner that its mouth is situated within said boiler below the water level. When the valve arranged in the valve housing t is opened, high-pressure steam flows through the conduit to into the low-pressure boiler B and is mixed with the water in that boiler. In the preferred embodiment of my invention the valve is provided with a handle manually operable from the engineers cab, as shown in Fig. 1. In Fig. 2 the manually controlled valve is represented on an enlarged scale in section. The handle comprises a hand wheel 2 which is mounted on a valve shaft 00. The valve shaft m provided with the thread I) is supported within the housing 25. When the hand Wheel 2 is turned, the shaft is shifted lengthwise and the valve member a is correspondingly lifted from, or pressed upon, its seat.

Fig. 3 represents an alternative control mechanism constructed as an automatic spring-controlled valve. Within the housing t the seating member a is shiftably supported and subjected to the pressure of the spring 0, tending to press it on its seat there-. by closing the passage between the steam drum 6 and the housing If. The spring a is so designed or adjusted that its pressure is overcome by the steam pressure in the water tube boiler as soon as the pressure in the'latter exceeds the pressure prevailing in the low-pressure boiler and in the valve housing by more than a predetermined amount.

The spring 0 is so adjusted that it permits its valve to open at a pressure which is lower than the pressure at which the required safety valve (not shown) would blow off. As soon as the valve a is opened by an excessive steam pressure in the steam receptacle e, the surplus of steam flows through the pipe u into the water space of the lowpressure boiler B whereby additional heat is transferred to, and steam produced in, said boiler.

In the case of the provision of a manually controlled valve, as shown in Fig. 2, the engineer of the locomotive can open the control valve when he wishes to accelerate the development of steam in the low-pressure boiler, provided a sufiicient steam pressure exists inthe high-pressure boiler, and he should open the control valve (Fig. 2) when the pressure gauge indicates that the steam pressure ,of the high-pressure boiler approaches the allowable pressure limit set by the safety valve. As soon as the pressure in In testimony whereof I have hereunto set w heating a separate relatively large confined pressure steam need be blown off into the atmosphere, thus avoiding loss of valuable energy.

I claim: I 1. The improvement in the generation of steam for use in multi-stage steam engines which comprises heating a confined body of water by the hot combustion gases of a fur.- nace so as to generate high-pressure steam from said water, heating a separate confined 7 body of water by the cooler flue gases of such furnaceso as to generate low-pressure steam therefrom, and conducting a portion of the high-pressure steam into said separate body of water to'accelerate the-generation of steam therefrom.

2. The'improvement in the generation of steam for use'in multi-stalge steam engines,

which comprise heating a relativelysmall- I confined body of water by the hot combustion gases of a furnace so as to generate rapidly h1gh-pressure. steam from 831d water,

body of -Water by the cooler flue gases of fan such furnace so as to. generate low-pressure steam therefrom, and conducting a portionof the high-pressure. steam into said separate body'of water to accelerate of steam therefrom. M

3. A steam generating plant comprising two boilers, one adapted to generate steam the generation of a higher pressure than the other, a com- -mon furnace for heating said boilers, the

high pressure boiler being heated by' the combustion gases and the low pressure boiler mon furnace for heating said boilers, the

high pressure boilerbeing heated by the combustion gases "and the low-pressure boiler being heated by the fiuegases of said furname, a conduit leading from thefsteam space my hand.

of-the .high pressure boiler to the water .space of' the low-pressure boiler, a valve 1n said conduit and mechanism for controlling the, opening and closing of 'saidvalve', sai mechanism being arranged to be manually" operated.

o'rro H. HART-MANN." 

